Pathological Laughter and Crying

Patients with PLC can have episodes of uncontrollable laughter, crying or both. Their emotional response may not indicate how they are actually feeling. They may start laughing or crying suddenly, either with or without a reason or trigger. When there is a trigger, usually their response is excessive: for example, if they would have smiled at something before the onset of PLC, now they may double over with laughter. 

Scientists say that PLC may be associated with disturbances in the prefrontal cortex or the neurological pathways in the brain that control emotional responses. Researchers have also suggested the serotonergic (related to serotonin or the happiness hormone) dysfunction may be responsible.

Though the exact physiopathology of PLC is not yet known, researchers have found that some people living with PLC also have other neurological problems, such as:

• Amyotrophic lateral sclerosis (ALS)
• Parkinson’s disease
• Traumatic  brain injury
• Multiple sclerosis
• Dementia
• Brain tumours

Diagnosis of pathological laughter and crying is done by a neurological expert, usually based on the patient's medical history and their reporting of symptoms. In patients who report inability to control their emotional responses, a mental health expert may also recommend an electroencephalogram (EEG) test to confirm a diagnosis.

Internationally, diagnosticians use tools like the Pathological Laughter and Crying Scale and the Center for Neurologic Study-Lability Scale to record frequency, duration and patients’ control over the episodes of laughter or crying.

The underlying mechanism of the disease is not yet known. So, doctors treat for the symptoms. In India, doctors have used antidepressants to manage PLC with limited success. The US Food & Drug Administration has recommended Nuedexta as first-line medicine for PLC.

Early diagnosis and management of PLC are important as patients can often feel embarrassed and can feel cut-off from society.

PLC is a rare disorder, with little public awareness around it. When a patient has a PLC event, the situation can quickly turn awkward. This can lead to embarrassment and social isolation.

In addition to proper medication, people living with PLC can try these methods to navigate social expectations: 

• Be open about your condition. Talk to people about it, and do not leave them confused
• Try to distract yourself with work, play, a movie - anything that takes up all your attention - as soon as you feel like laughing or crying without adequate reason. Counting backwards can help some patients avoid a PLC event. Of course, the success of these techniques will depend on how much voluntary control you have over your emotional expressions 
• Breathing techniques have also been known to help some people living with PLC. When you feel like laughing or crying, move to a calm and quiet place. Sit down and breathe slowly. Try focusing on your breathing to distract yourself
• Do not berate yourself - this is a medical condition and it’s out of your control. Talk to a friend, family member or psychologist to help you when you’re feeling blue 
• After a PLC episode is over, do not return to your routine immediately. Take a few minutes to rest. Try putting your head down for a minute to relax